Civil Engineering - Highway Engineering - Discussion

Discussion Forum : Highway Engineering - Section 2 (Q.No. 23)
23.
The absolute minimum sight distance required for stopping a vehicle moving with a speed of 80 km ph, is
120 m
200 m
640 m
none of these.
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
15 comments Page 1 of 2.

Ajay Sharma said:   5 years ago
This value is given directly in form of table.

For 80kmph = 120m.
(1)

Dipunku said:   5 years ago
The correct answer is 127.6m.

Mayu said:   5 years ago
Longitudinal friction --------- 0.35 - 0.4.
Lateral friction --------------- 0.15.
(2)

Lucky Kumar said:   6 years ago
SSD = 0.278Vt+V^2/254(f+S%).
= 0.278*80*2.5+80*80/254(.35).
= 127.6 mtr.

Cofficent of friction (f) = 0.35.
(1)

Dinesh said:   6 years ago
0.28 * V.t + 0.01V^2/brake efficiency.
V = 80
t = 2.5
And We get exact ans 120.
(1)

Shubham said:   7 years ago
Right @Navi.
(2)

Pakkirappa said:   8 years ago
V is given in kmph convert to m
I.e 1000/60*60=0.278
Ssd=vt+{v2/2gf}
Where t is time required for understanding the situation this is a constant value.
Ssd=0.27*80*2.5+{(0.27*80)^2/(2*9.81*0.35)}
Ssd=121.6m.
(4)

ANKUR said:   8 years ago
We can predict because we have to calculate min SSD if take f= .15 we get more value but if we take f= .35 we get min value so we take f=.35.
(1)

Asita said:   9 years ago
Yes, right @Navi.
(1)

Ankur said:   9 years ago
How to predict the value of f in such cases?


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